Knife-edge bearing



Dec. 30, 1930. R, c U 1,786,424

KNIFE EDGE BEARING Filed Oct. 20, 1928 A 5 c P --+------1 l .y

Patented Dec. 30, 1930 UNETD STATES ATNT RENE FR-ANQOIS HENRI GAILLAUD, OF ST. MAURICE, FRANCE, ASSIGNOR TO SOCIETE ANONYME DES ETABLISSEMENTS LUTER-AAN, F PARIS, FRANCE KNIFE-EDGE BEARING Application filed October 20, 1928, Serial No. 313,835, and in France November 7, 1927.

wear may cause differences in the axial position, it is desired to obviate these two defects.

However, in the known construction of knlfe edges and the mounting of the same upon the levers the device cannot be adjusted at the same time for the level and for the axial position.

The present invention relates to a method of mounting of the knives by which the device can be adjusted simultaneously for the level and for the axial position.

The said method is essentially characterized by the fact that the knives are mounted upon their supporting lever by means of a mechanical connecting oevice so disposed that by its adjustment, the axis of the knives may be given displacements relatively to axes of coordinates placed at right angles, whose origin is situated upon the axis of the assembling holes of the corresponding lever.

In the appended drawings and by way of example:

Fig. 1 shows the known arrangement of a triangular knife edge, and Fig. 2 shows the same on a larger scale.

Fig. 3 shows a modification of this device in which the knife edge may be rotated for the adjustment of the axial position.

Fig. 4 is a front view of the knife edge.

Figs. 5 and 6 show a cross section of the lever and of the tapered shank for securing the knife.

Fig. 7 shows the device according to the invention.

Figs. 8 and 9 represent a front view of the knife and a cross section of the lever, as well as the arrangements for changing the position of the said knife.

As arule, the triangular knife edge 1 is driven by tight friction into a lever or scale beam 2 which is provided for the purpose with a dovetail mortise (Fig. 2).

After grinding one or both sides of the knife edge 1 when the edge has become worn, it will be impossible to place the edge at the centre and at the proper level by mechanical means, so that the scale beam must be bent by impact or pressure, although both these means are unadvisable from a mechanical standpoint.

Attempts have been made to partially obviate these defects by mounting the knife edge by means of a tapered joint (Figs. 4, 5 andfi) and herein the knife edge 1 is provided with a tapered shank adapted for insertioninto a recess l of like shape which is formed in the lever 2.

.This arrangement is superior to the preceding since the device can be centered by turning the knife 1 according to the arrows at a (Fig. 4) about the axis z.2 of its recess 4: in the lever 2. Due to this freedom of mo- .tion the axial position can be properly regulated, but the device can only be adjusted for the level by the permanent deformation of the lever by shocks or pressure.

The'arrangement according to the invention permits the adj ustment of the axial position and of the levelat the same time. For this purpose, I dispose between the recess 4 of the lever 2 and the shank 3 of the knife edge 1, a connecting device having two different motions, so that the displacements of said device relatively to the lever 2 will cause the movements of the axis of the said shank of the knife blade with reference to two rectilinear axes of co-ordinates b 0 whose pointof origin 0 is situated on the axis 2a of the said recess 4 of the lever 2.

By way of example, the apparatus may be constructed as follows.

In the recess 4 of the lever 2 is disposed a ring 5 which has a cylindrical form at the exterior and is provided with a tapered hole 6 in eccentric relation to the outer circumference of the ring 5. The knife edge 1 is provided with a tapered shank 3 having at the end the round threaded part 7. The smooth portion 3 is adapted for an exact fit with the hole 6 of the said ring; the threaded part 7 extends outwardly of the latter, so that the knife edge 1 may be securely held by the nut 8 mounted on the said threaded end 7 of the knife edge.

The ring 5 is split upon a single generatrix in order to provide a tight fit upon the round part of the ring 5 and also upon the tapered part of the knife edge.

The device is mounted as follows:

(a) The knife is mounted with the edge at the top. The knife 1 is so disposed that the smallest thickness of the eccentric ring is at the lower part (Fig. 8). Should it be necessary to make repairs due to the Wear of the knife edge, the edge of the knife 1 can be sharpened by grinding on a stone. WVhen this operation has been performed, the nut S holding the knife in its recess is loosened, and said knife is turned so as to properly adjust the axial position, at the same time rotating the ring 5 to the proper degree for the adjustment of the level with reference to the other knife edges of the same lever l. Bvthis simple means I obviate all bending of the scale beam according to the usual method.

(7)) The knife is mounted With the edge at the bottom. The knife is so disposed that the smallest thickness of the eccentric ring 5 is at the upper part, and the rest of the operation is performed as above mentioned.

I claim:

The combination of a knife edge With an eccentric bearing support comprising a main support having a circular opening therein, a bearing sleeve mounted in said opening and having an opening eccentric to said first men tioned opening, a knife edge having a tapered shank fitting said opening, and means for securing said tapered shank in the opening in any angular position, whereby by turning both the bearing sleeve and knife edge said ed e may be moved in a vertical direction.

in testimony whereof I afiix my signature.

RENE FRANCOIS HENRI CAlLLAUD. 

